Wednesday, July 21, 2010

The (non-)role of mirror neurons: Greg Hickok's new critical review

An important new paper by the tireless Greg (guess on which topic ... :-) has just appeared in the journal Language and Cognitive Processes -- Cognitive Neuroscience of Language (which, yes, I edit). The paper is called "The role of mirror neurons in speech perception and action word semantics" and has just been picked up by the very popular BPS Research Digest.

Here is the abstract:

The discovery of mirror neurons in the macaque monkey has ignited intense interest in motor theories of cognition, including speech and language. Here we examine two such claims, that the perception of speech sounds critically depends on motor representations of speech gestures (the motor theory of speech perception) and that the representation of action-related semantic knowledge critically depends on motor representations involved in performing actions. We conclude that there is strong evidence against the claim that speech perception critically depends on the motor system and that there is no conclusive evidence in support of the view that the motor system supports action semantics. We propose instead that motor-related activity during perceptual processes stem from spreading activation in sensory-motor networks that are critical for speech and language production.

The publisher of the journal has made this paper free to read until August 15. Run -- don't walk -- to your nearest computer and read this next installment (after Greg's "8 Problems" paper from 2009) of Greg's arguments for resisting the mirror neuron juggernaut.

Then write a brilliant paper on some aspect of the cognitive neuroscience of language (does not even have to be mirror neuron related, promise) and submit it to the journal.


Anonymous said...

I don't mean to split hairs, but this paper (as with '8 problems') seems to be conflating 1) whether mirror neurons exist 2) what mirror neurons 'do'.

I'm sure this is unintended, because Greg has said on this blog that he would be surprised if mirror neurons did not exist in humans.

Just an example of what I'm talking about:

In the section "mirror neurons in humans?" Greg cites both evidence from fMRI and evidence from apraxia. The fMRI literature is evidence for the *existence* of MNs while the apraxia studies are evidence for the cognitive *function* of MNs.

Greg Hickok said...

I think you are right that there is some ambiguity in the way I presented some of my arguments. I'm not arguing against the existence of something like mirror neurons in humans. In fact I suspect cells with mirror properties will eventually be found in a range of mammals and birds (already there is behavioral evidence suggesting they exist in domestic dogs). What I intended to contest was the claim that this system is the basis of "understanding".